China's top offshore oil producer posted a net profit of
34.38 billion yuan ($5.61 billion) for January-June, compared
with 31.87 billion yuan a year earlier and topping the average
forecast of 30.87 billion yuan in a Reuters poll of four
analysts.

Oil and gas output jumped 23.1 percent on year to 198.1
million barrels of oil equivalent (BOE) in the first six months,
including 24.8 million BOE from Nexen, CNOOC said in a filing
with the Hong Kong stock exchange on Tuesday.

CNOOC said previously the acquisition of Nexen - the biggest
ever overseas corporate takeover by a Chinese company - would
boost its production by 20 percent and increase its proven
reserves by 30 percent.

Excluding the output contribution from Nexen, production
rose 7.7 percent to 173.3 million BOE as CNOOC's Penglai 19-3
oilfield in eastern China's Bohai Bay resumed production
following an oil spill in 2011. Its projects in the United
States and Iraq were also "an important source of production
growth" for the company, it said.

The impact of the output increase was partly offset by
slightly lower oil prices and higher costs, CNOOC said. Like
many other oil companies in the world, CNOOC has been facing
rising costs as it widens its exposure to unconventional energy
such as oil sands.

The company, which declared an interim dividend of HK$0.25
per share for the first half, said its integration with Nexen
was proceeding smoothly and that CNOOC has been "actively"
working on its application for a secondary listing on the
Toronto Stock Exchange.

To win Canadian approvals for the Nexen takeover, CNOOC made
a series of commitments like retaining all Nexen staff, pursuing
a listing in Toronto and making Calgary the headquarters of its
$8 billion North and Central American operations.